The present invention relates to a cartridge for launching decoy material, comprising sets of decoy payloads arranged along the longitudinal direction of the cartridge.
Decoy material is understood to include material which reflects electromagnetic waves like radar waves, infrared waves, sonor waves, microwaves, and flares etc.
Cartridges containing cassettes with more than one decoy payloads are previously known from U.S. Pat. No. 4,178,854 and published Swedish patent application 7514020-2.
The U.S. patent describes a rocket type cartridge with a frangible wall which is sectionally split by explosives for each payload unit. The payload sections of each payload unit are blown outwardly in a radial direction by explosives. Further explosives are used to disperse the decoy material from the sections. The known cartridge is relatively complicated and volatile because of the necessity of splitting the cartridge wall and there is a substantial risk of damaging the decoys. A further drawback is that there is no way to control the ejection of the sections of a payload unit in an arbritary time sequence. But instead all of the sections of each payload unit are blown away simultaneously. A still further drawback is that the payload units must be located in a rocket to effect movement of the sections in the longitudinal direction of the cartridge in order to obtain the desired character of the dispersion.
The Swedish patent application describes a cartridge having payloads arranged one behind the other in the ejction direction. The payloads are ejected one by one in a sequence determined by their positions relative to the exit of the cartridige. One drawback of this cartridge is that there is no possibility to choose payloads for ejection. The payload situated closest to the exit must always be ejected first, even if a different type of decoy would create the counter-measure effect needed. Another drawback of this cartridge is that it only contains a very limited number of payloads. A great number of payloads in a row would make it difficult to obtain a reliable ejection of the payloads, and the cartridge would not have a suitable length. Among other consequences, the elongated transmission network of conductors and connecting devices required would contribute to the unreliability of such an elongated cartridge.